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lib.rs
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//! This crate provides two major things:
//!
//! 1. The types served by the `http_api` crate.
//! 2. A wrapper around `reqwest` that forms a HTTP client, able of consuming the endpoints served
//! by the `http_api` crate.
//!
//! Eventually it would be ideal to publish this crate on crates.io, however we have some local
//! dependencies preventing this presently.
#[cfg(feature = "lighthouse")]
pub mod lighthouse;
pub mod types;
use self::types::*;
use reqwest::{IntoUrl, Response};
use serde::{de::DeserializeOwned, Serialize};
use std::convert::TryFrom;
use std::fmt;
pub use reqwest;
pub use reqwest::{StatusCode, Url};
#[derive(Debug)]
pub enum Error {
/// The `reqwest` client raised an error.
Reqwest(reqwest::Error),
/// The server returned an error message where the body was able to be parsed.
ServerMessage(ErrorMessage),
/// The server returned an error message where the body was unable to be parsed.
StatusCode(StatusCode),
/// The supplied URL is badly formatted. It should look something like `http://127.0.0.1:5052`.
InvalidUrl(Url),
}
impl Error {
/// If the error has a HTTP status code, return it.
pub fn status(&self) -> Option<StatusCode> {
match self {
Error::Reqwest(error) => error.status(),
Error::ServerMessage(msg) => StatusCode::try_from(msg.code).ok(),
Error::StatusCode(status) => Some(*status),
Error::InvalidUrl(_) => None,
}
}
}
impl fmt::Display for Error {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{:?}", self)
}
}
/// A wrapper around `reqwest::Client` which provides convenience methods for interfacing with a
/// Lighthouse Beacon Node HTTP server (`http_api`).
#[derive(Clone)]
pub struct BeaconNodeClient {
client: reqwest::Client,
server: Url,
}
impl BeaconNodeClient {
/// Returns `Err(())` if the URL is invalid.
pub fn new(server: Url) -> Self {
Self {
client: reqwest::Client::new(),
server,
}
}
/// Returns `Err(())` if the URL is invalid.
pub fn from_components(server: Url, client: reqwest::Client) -> Self {
Self { client, server }
}
/// Return the path with the standard `/eth1/v1` prefix applied.
fn eth_path(&self) -> Result<Url, Error> {
let mut path = self.server.clone();
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("eth")
.push("v1");
Ok(path)
}
/// Perform a HTTP GET request.
async fn get<T: DeserializeOwned, U: IntoUrl>(&self, url: U) -> Result<T, Error> {
let response = self.client.get(url).send().await.map_err(Error::Reqwest)?;
ok_or_error(response)
.await?
.json()
.await
.map_err(Error::Reqwest)
}
/// Perform a HTTP GET request, returning `None` on a 404 error.
async fn get_opt<T: DeserializeOwned, U: IntoUrl>(&self, url: U) -> Result<Option<T>, Error> {
let response = self.client.get(url).send().await.map_err(Error::Reqwest)?;
match ok_or_error(response).await {
Ok(resp) => resp.json().await.map(Option::Some).map_err(Error::Reqwest),
Err(err) => {
if err.status() == Some(StatusCode::NOT_FOUND) {
Ok(None)
} else {
Err(err)
}
}
}
}
/// Perform a HTTP POST request.
async fn post<T: Serialize, U: IntoUrl>(&self, url: U, body: &T) -> Result<(), Error> {
let response = self
.client
.post(url)
.json(body)
.send()
.await
.map_err(Error::Reqwest)?;
ok_or_error(response).await?;
Ok(())
}
/// `GET beacon/genesis`
///
/// ## Errors
///
/// May return a `404` if beacon chain genesis has not yet occurred.
pub async fn get_beacon_genesis(&self) -> Result<GenericResponse<GenesisData>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("genesis");
self.get(path).await
}
/// `GET beacon/states/{state_id}/root`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_states_root(
&self,
state_id: StateId,
) -> Result<Option<GenericResponse<RootData>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("states")
.push(&state_id.to_string())
.push("root");
self.get_opt(path).await
}
/// `GET beacon/states/{state_id}/fork`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_states_fork(
&self,
state_id: StateId,
) -> Result<Option<GenericResponse<Fork>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("states")
.push(&state_id.to_string())
.push("fork");
self.get_opt(path).await
}
/// `GET beacon/states/{state_id}/finality_checkpoints`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_states_finality_checkpoints(
&self,
state_id: StateId,
) -> Result<Option<GenericResponse<FinalityCheckpointsData>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("states")
.push(&state_id.to_string())
.push("finality_checkpoints");
self.get_opt(path).await
}
/// `GET beacon/states/{state_id}/validators`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_states_validators(
&self,
state_id: StateId,
) -> Result<Option<GenericResponse<Vec<ValidatorData>>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("states")
.push(&state_id.to_string())
.push("validators");
self.get_opt(path).await
}
/// `GET beacon/states/{state_id}/committees?slot,index`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_states_committees(
&self,
state_id: StateId,
epoch: Epoch,
slot: Option<Slot>,
index: Option<u64>,
) -> Result<Option<GenericResponse<Vec<CommitteeData>>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("states")
.push(&state_id.to_string())
.push("committees")
.push(&epoch.to_string());
if let Some(slot) = slot {
path.query_pairs_mut()
.append_pair("slot", &slot.to_string());
}
if let Some(index) = index {
path.query_pairs_mut()
.append_pair("index", &index.to_string());
}
self.get_opt(path).await
}
/// `GET beacon/states/{state_id}/validators/{validator_id}`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_states_validator_id(
&self,
state_id: StateId,
validator_id: &ValidatorId,
) -> Result<Option<GenericResponse<ValidatorData>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("states")
.push(&state_id.to_string())
.push("validators")
.push(&validator_id.to_string());
self.get_opt(path).await
}
/// `GET beacon/headers?slot,parent_root`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_headers(
&self,
slot: Option<Slot>,
parent_root: Option<Hash256>,
) -> Result<Option<GenericResponse<Vec<BlockHeaderData>>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("headers");
if let Some(slot) = slot {
path.query_pairs_mut()
.append_pair("slot", &slot.to_string());
}
if let Some(root) = parent_root {
path.query_pairs_mut()
.append_pair("parent_root", &format!("{:?}", root));
}
self.get_opt(path).await
}
/// `GET beacon/headers/{block_id}`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_headers_block_id(
&self,
block_id: BlockId,
) -> Result<Option<GenericResponse<BlockHeaderData>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("headers")
.push(&block_id.to_string());
self.get_opt(path).await
}
/// `POST beacon/blocks`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn post_beacon_blocks<T: EthSpec>(
&self,
block: &SignedBeaconBlock<T>,
) -> Result<(), Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("blocks");
self.post(path, block).await?;
Ok(())
}
/// `GET beacon/blocks`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_blocks<T: EthSpec>(
&self,
block_id: BlockId,
) -> Result<Option<GenericResponse<SignedBeaconBlock<T>>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("blocks")
.push(&block_id.to_string());
self.get_opt(path).await
}
/// `GET beacon/blocks/{block_id}/root`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_blocks_root(
&self,
block_id: BlockId,
) -> Result<Option<GenericResponse<RootData>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("blocks")
.push(&block_id.to_string())
.push("root");
self.get_opt(path).await
}
/// `GET beacon/blocks/{block_id}/attestations`
///
/// Returns `Ok(None)` on a 404 error.
pub async fn get_beacon_blocks_attestations<T: EthSpec>(
&self,
block_id: BlockId,
) -> Result<Option<GenericResponse<Vec<Attestation<T>>>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("blocks")
.push(&block_id.to_string())
.push("attestations");
self.get_opt(path).await
}
/// `POST beacon/pool/attestations`
pub async fn post_beacon_pool_attestations<T: EthSpec>(
&self,
attestation: &Attestation<T>,
) -> Result<(), Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("pool")
.push("attestations");
self.post(path, attestation).await?;
Ok(())
}
/// `GET beacon/pool/attestations`
pub async fn get_beacon_pool_attestations<T: EthSpec>(
&self,
) -> Result<GenericResponse<Vec<Attestation<T>>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("pool")
.push("attestations");
self.get(path).await
}
/// `POST beacon/pool/attester_slashings`
pub async fn post_beacon_pool_attester_slashings<T: EthSpec>(
&self,
slashing: &AttesterSlashing<T>,
) -> Result<(), Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("pool")
.push("attester_slashings");
self.post(path, slashing).await?;
Ok(())
}
/// `GET beacon/pool/attester_slashings`
pub async fn get_beacon_pool_attester_slashings<T: EthSpec>(
&self,
) -> Result<GenericResponse<Vec<AttesterSlashing<T>>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("pool")
.push("attester_slashings");
self.get(path).await
}
/// `POST beacon/pool/proposer_slashings`
pub async fn post_beacon_pool_proposer_slashings(
&self,
slashing: &ProposerSlashing,
) -> Result<(), Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("pool")
.push("proposer_slashings");
self.post(path, slashing).await?;
Ok(())
}
/// `GET beacon/pool/proposer_slashings`
pub async fn get_beacon_pool_proposer_slashings(
&self,
) -> Result<GenericResponse<Vec<ProposerSlashing>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("pool")
.push("proposer_slashings");
self.get(path).await
}
/// `POST beacon/pool/voluntary_exits`
pub async fn post_beacon_pool_voluntary_exits(
&self,
exit: &SignedVoluntaryExit,
) -> Result<(), Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("pool")
.push("voluntary_exits");
self.post(path, exit).await?;
Ok(())
}
/// `GET beacon/pool/voluntary_exits`
pub async fn get_beacon_pool_voluntary_exits(
&self,
) -> Result<GenericResponse<Vec<SignedVoluntaryExit>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("beacon")
.push("pool")
.push("voluntary_exits");
self.get(path).await
}
/// `GET config/fork_schedule`
pub async fn get_config_fork_schedule(&self) -> Result<GenericResponse<Vec<Fork>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("config")
.push("fork_schedule");
self.get(path).await
}
/// `GET config/fork_schedule`
pub async fn get_config_spec(&self) -> Result<GenericResponse<YamlConfig>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("config")
.push("spec");
self.get(path).await
}
/// `GET config/deposit_contract`
pub async fn get_config_deposit_contract(
&self,
) -> Result<GenericResponse<DepositContractData>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("config")
.push("deposit_contract");
self.get(path).await
}
/// `GET node/version`
pub async fn get_node_version(&self) -> Result<GenericResponse<VersionData>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("node")
.push("version");
self.get(path).await
}
/// `GET node/syncing`
pub async fn get_node_syncing(&self) -> Result<GenericResponse<SyncingData>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("node")
.push("syncing");
self.get(path).await
}
/// `GET debug/beacon/states/{state_id}`
pub async fn get_debug_beacon_states<T: EthSpec>(
&self,
state_id: StateId,
) -> Result<Option<GenericResponse<BeaconState<T>>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("debug")
.push("beacon")
.push("states")
.push(&state_id.to_string());
self.get_opt(path).await
}
/// `GET debug/beacon/heads`
pub async fn get_debug_beacon_heads(
&self,
) -> Result<GenericResponse<Vec<ChainHeadData>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("debug")
.push("beacon")
.push("heads");
self.get(path).await
}
/// `GET validator/duties/attester/{epoch}?index`
///
/// ## Note
///
/// The `index` query parameter accepts a list of validator indices.
pub async fn get_validator_duties_attester(
&self,
epoch: Epoch,
index: Option<&[u64]>,
) -> Result<GenericResponse<Vec<AttesterData>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("validator")
.push("duties")
.push("attester")
.push(&epoch.to_string());
if let Some(index) = index {
let string = index
.iter()
.map(|i| i.to_string())
.collect::<Vec<_>>()
.join(",");
path.query_pairs_mut().append_pair("index", &string);
}
self.get(path).await
}
/// `GET validator/duties/proposer/{epoch}`
pub async fn get_validator_duties_proposer(
&self,
epoch: Epoch,
) -> Result<GenericResponse<Vec<ProposerData>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("validator")
.push("duties")
.push("proposer")
.push(&epoch.to_string());
self.get(path).await
}
/// `GET validator/duties/attester/{epoch}?index`
///
/// ## Note
///
/// The `index` query parameter accepts a list of validator indices.
pub async fn get_validator_blocks<T: EthSpec>(
&self,
slot: Slot,
randao_reveal: SignatureBytes,
graffiti: Option<&Graffiti>,
) -> Result<GenericResponse<BeaconBlock<T>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("validator")
.push("blocks")
.push(&slot.to_string());
path.query_pairs_mut()
.append_pair("randao_reveal", &randao_reveal.to_string());
if let Some(graffiti) = graffiti {
path.query_pairs_mut()
.append_pair("graffiti", &graffiti.to_string());
}
self.get(path).await
}
/// `GET validator/attestation_data?slot,committee_index`
pub async fn get_validator_attestation_data(
&self,
slot: Slot,
committee_index: CommitteeIndex,
) -> Result<GenericResponse<AttestationData>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("validator")
.push("attestation_data");
path.query_pairs_mut()
.append_pair("slot", &slot.to_string())
.append_pair("committee_index", &committee_index.to_string());
self.get(path).await
}
/// `GET validator/attestation_data?slot,committee_index`
pub async fn get_validator_aggregate_attestation<T: EthSpec>(
&self,
slot: Slot,
attestation_data_root: Hash256,
) -> Result<Option<GenericResponse<Attestation<T>>>, Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("validator")
.push("aggregate_attestation");
path.query_pairs_mut()
.append_pair("slot", &slot.to_string())
.append_pair(
"attestation_data_root",
&format!("{:?}", attestation_data_root),
);
self.get_opt(path).await
}
/// `POST validator/aggregate_and_proofs`
pub async fn post_validator_aggregate_and_proof<T: EthSpec>(
&self,
aggregate: &SignedAggregateAndProof<T>,
) -> Result<(), Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("validator")
.push("aggregate_and_proofs");
self.post(path, aggregate).await?;
Ok(())
}
/// `POST validator/beacon_committee_subscriptions`
pub async fn post_validator_beacon_committee_subscriptions(
&self,
subscriptions: &[BeaconCommitteeSubscription],
) -> Result<(), Error> {
let mut path = self.eth_path()?;
path.path_segments_mut()
.map_err(|()| Error::InvalidUrl(self.server.clone()))?
.push("validator")
.push("beacon_committee_subscriptions");
self.post(path, &subscriptions).await?;
Ok(())
}
}
/// Returns `Ok(response)` if the response is a `200 OK` response. Otherwise, creates an
/// appropriate error message.
async fn ok_or_error(response: Response) -> Result<Response, Error> {
let status = response.status();
if status == StatusCode::OK {
Ok(response)
} else if let Ok(message) = response.json().await {
Err(Error::ServerMessage(message))
} else {
Err(Error::StatusCode(status))
}
}